Corrosion Evaluation of MgCaZn Biodegradable Alloys

In recent years, biodegradable materials have featured magnesium alloys with uniform disintegration and a defined disintegration rate. Despite their promising mechanical features, magnesium alloys’ low corrosion resistance limits their use. Alloying is an effective way of improving the corrosion resistance of Mg alloys. In this paper, the corrosion behavior of Mg-Ca-Zn alloys with 1 wt.% and 2 wt.% Zn content is investigated by light microscopy and electrochemical analysis. The results indicated relatively uniform polyhedric Mg grains containing a lamellar Mg2Ca compound highlighted at the grain boundary. The inclusion of Zn considerably reduces the susceptibility to corrosion of the Mg-Zn-Ca alloy, mostly through the formation of micro galvanic couples from the more common secondary phase particles.